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  <div class="section" id="complex-number-objects">
<span id="complexobjects"></span><h1>Complex Number Objects<a class="headerlink" href="#complex-number-objects" title="Permalink to this headline">¶</a></h1>
<p id="index-0">Python’s complex number objects are implemented as two distinct types when
viewed from the C API:  one is the Python object exposed to Python programs, and
the other is a C structure which represents the actual complex number value.
The API provides functions for working with both.</p>
<div class="section" id="complex-numbers-as-c-structures">
<h2>Complex Numbers as C Structures<a class="headerlink" href="#complex-numbers-as-c-structures" title="Permalink to this headline">¶</a></h2>
<p>Note that the functions which accept these structures as parameters and return
them as results do so <em>by value</em> rather than dereferencing them through
pointers.  This is consistent throughout the API.</p>
<dl class="type">
<dt id="c.Py_complex">
<code class="descname">Py_complex</code><a class="headerlink" href="#c.Py_complex" title="Permalink to this definition">¶</a></dt>
<dd><p>The C structure which corresponds to the value portion of a Python complex
number object.  Most of the functions for dealing with complex number objects
use structures of this type as input or output values, as appropriate.  It is
defined as:</p>
<div class="highlight-c"><div class="highlight"><pre><span></span><span class="k">typedef</span> <span class="k">struct</span> <span class="p">{</span>
   <span class="kt">double</span> <span class="n">real</span><span class="p">;</span>
   <span class="kt">double</span> <span class="n">imag</span><span class="p">;</span>
<span class="p">}</span> <span class="n">Py_complex</span><span class="p">;</span>
</pre></div>
</div>
</dd></dl>

<dl class="function">
<dt id="c._Py_c_sum">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">_Py_c_sum</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;left</em>, <a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;right</em><span class="sig-paren">)</span><a class="headerlink" href="#c._Py_c_sum" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the sum of two complex numbers, using the C <a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a>
representation.</p>
</dd></dl>

<dl class="function">
<dt id="c._Py_c_diff">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">_Py_c_diff</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;left</em>, <a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;right</em><span class="sig-paren">)</span><a class="headerlink" href="#c._Py_c_diff" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the difference between two complex numbers, using the C
<a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a> representation.</p>
</dd></dl>

<dl class="function">
<dt id="c._Py_c_neg">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">_Py_c_neg</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;complex</em><span class="sig-paren">)</span><a class="headerlink" href="#c._Py_c_neg" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the negation of the complex number <em>complex</em>, using the C
<a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a> representation.</p>
</dd></dl>

<dl class="function">
<dt id="c._Py_c_prod">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">_Py_c_prod</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;left</em>, <a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;right</em><span class="sig-paren">)</span><a class="headerlink" href="#c._Py_c_prod" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the product of two complex numbers, using the C <a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a>
representation.</p>
</dd></dl>

<dl class="function">
<dt id="c._Py_c_quot">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">_Py_c_quot</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;dividend</em>, <a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;divisor</em><span class="sig-paren">)</span><a class="headerlink" href="#c._Py_c_quot" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the quotient of two complex numbers, using the C <a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a>
representation.</p>
<p>If <em>divisor</em> is null, this method returns zero and sets
<code class="xref c c-data docutils literal"><span class="pre">errno</span></code> to <code class="xref c c-data docutils literal"><span class="pre">EDOM</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c._Py_c_pow">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">_Py_c_pow</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;num</em>, <a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;exp</em><span class="sig-paren">)</span><a class="headerlink" href="#c._Py_c_pow" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the exponentiation of <em>num</em> by <em>exp</em>, using the C <a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a>
representation.</p>
<p>If <em>num</em> is null and <em>exp</em> is not a positive real number,
this method returns zero and sets <code class="xref c c-data docutils literal"><span class="pre">errno</span></code> to <code class="xref c c-data docutils literal"><span class="pre">EDOM</span></code>.</p>
</dd></dl>

</div>
<div class="section" id="complex-numbers-as-python-objects">
<h2>Complex Numbers as Python Objects<a class="headerlink" href="#complex-numbers-as-python-objects" title="Permalink to this headline">¶</a></h2>
<dl class="type">
<dt id="c.PyComplexObject">
<code class="descname">PyComplexObject</code><a class="headerlink" href="#c.PyComplexObject" title="Permalink to this definition">¶</a></dt>
<dd><p>This subtype of <a class="reference internal" href="structures.html#c.PyObject" title="PyObject"><code class="xref c c-type docutils literal"><span class="pre">PyObject</span></code></a> represents a Python complex number object.</p>
</dd></dl>

<dl class="var">
<dt id="c.PyComplex_Type">
<a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject">PyTypeObject</a> <code class="descname">PyComplex_Type</code><a class="headerlink" href="#c.PyComplex_Type" title="Permalink to this definition">¶</a></dt>
<dd><p>This instance of <a class="reference internal" href="type.html#c.PyTypeObject" title="PyTypeObject"><code class="xref c c-type docutils literal"><span class="pre">PyTypeObject</span></code></a> represents the Python complex number
type. It is the same object as <a class="reference internal" href="../library/functions.html#complex" title="complex"><code class="xref py py-class docutils literal"><span class="pre">complex</span></code></a> in the Python layer.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_Check">
int <code class="descname">PyComplex_Check</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_Check" title="Permalink to this definition">¶</a></dt>
<dd><p>Return true if its argument is a <a class="reference internal" href="#c.PyComplexObject" title="PyComplexObject"><code class="xref c c-type docutils literal"><span class="pre">PyComplexObject</span></code></a> or a subtype of
<a class="reference internal" href="#c.PyComplexObject" title="PyComplexObject"><code class="xref c c-type docutils literal"><span class="pre">PyComplexObject</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_CheckExact">
int <code class="descname">PyComplex_CheckExact</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*p</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_CheckExact" title="Permalink to this definition">¶</a></dt>
<dd><p>Return true if its argument is a <a class="reference internal" href="#c.PyComplexObject" title="PyComplexObject"><code class="xref c c-type docutils literal"><span class="pre">PyComplexObject</span></code></a>, but not a subtype of
<a class="reference internal" href="#c.PyComplexObject" title="PyComplexObject"><code class="xref c c-type docutils literal"><span class="pre">PyComplexObject</span></code></a>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_FromCComplex">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyComplex_FromCComplex</code><span class="sig-paren">(</span><a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a><em>&nbsp;v</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_FromCComplex" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Create a new Python complex number object from a C <a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a> value.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_FromDoubles">
<a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a>* <code class="descname">PyComplex_FromDoubles</code><span class="sig-paren">(</span>double<em>&nbsp;real</em>, double<em>&nbsp;imag</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_FromDoubles" title="Permalink to this definition">¶</a></dt>
<dd><em class="refcount">Return value: New reference.</em><p>Return a new <a class="reference internal" href="#c.PyComplexObject" title="PyComplexObject"><code class="xref c c-type docutils literal"><span class="pre">PyComplexObject</span></code></a> object from <em>real</em> and <em>imag</em>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_RealAsDouble">
double <code class="descname">PyComplex_RealAsDouble</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*op</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_RealAsDouble" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the real part of <em>op</em> as a C <code class="xref c c-type docutils literal"><span class="pre">double</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_ImagAsDouble">
double <code class="descname">PyComplex_ImagAsDouble</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*op</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_ImagAsDouble" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the imaginary part of <em>op</em> as a C <code class="xref c c-type docutils literal"><span class="pre">double</span></code>.</p>
</dd></dl>

<dl class="function">
<dt id="c.PyComplex_AsCComplex">
<a class="reference internal" href="#c.Py_complex" title="Py_complex">Py_complex</a> <code class="descname">PyComplex_AsCComplex</code><span class="sig-paren">(</span><a class="reference internal" href="structures.html#c.PyObject" title="PyObject">PyObject</a><em>&nbsp;*op</em><span class="sig-paren">)</span><a class="headerlink" href="#c.PyComplex_AsCComplex" title="Permalink to this definition">¶</a></dt>
<dd><p>Return the <a class="reference internal" href="#c.Py_complex" title="Py_complex"><code class="xref c c-type docutils literal"><span class="pre">Py_complex</span></code></a> value of the complex number <em>op</em>.</p>
<p>If <em>op</em> is not a Python complex number object but has a <a class="reference internal" href="../reference/datamodel.html#object.__complex__" title="object.__complex__"><code class="xref py py-meth docutils literal"><span class="pre">__complex__()</span></code></a>
method, this method will first be called to convert <em>op</em> to a Python complex
number object. Upon failure, this method returns <code class="docutils literal"><span class="pre">-1.0</span></code> as a real value.</p>
</dd></dl>

</div>
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<li><a class="reference internal" href="#">Complex Number Objects</a><ul>
<li><a class="reference internal" href="#complex-numbers-as-c-structures">Complex Numbers as C Structures</a></li>
<li><a class="reference internal" href="#complex-numbers-as-python-objects">Complex Numbers as Python Objects</a></li>
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